Speed-counter.



C. E. SKINNER.

sPEEn COUNTER. APPLICATION FILED JUNE 14, 1912.

1,214,088. Patented Jan. 30, 1917.

2 SHEETS-SHEET l wlTNEssEs: lgEToR MQW# Y ATT'URNEY ,0. E. SKINNER.'

SPEED COUNTER.

APPLICATION HLn|uNE|4.19|2.

Patented Jan. 30, 1917.

2 SHEITS-SHEET 2.

: NTOR wlNEssEs:

ATTORNEY UNTTED sTATEs PATENT onirica.

CHARLES E. SKINNER, `OF WILKINSBUBG, PENNSYLVANIA, ASSIGNOB. TO WESTING- HOUSE ELECTRIC ANI) MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- vaina.

SPEED-COUNTER. l

Specication o! Letters IPatent.

Patented Jan. 30, 1.917.

Application led J' une 14, 1912. Serial No. 703,699.

To all whom it may concern.' I

Be it known that I, CHARLES E. SKINNER, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Speed-Counters, of which the following is a speciicatien.

My invention relates to means for determining the number of rotations of a shaft or other rotary object in a given time, and it has special reference to speed counters for ascertaining the number of rotations per minute of a rotating shaft.

The object of my invention is to provide a device of the class above indicated that shall be automatically started at the beginning and stopped at the end of a predetermined period of time.

A simple speed counter of a well known type comprises a shaft or spindlelwhich is' provided with a suitable point that. is adapt- `ed to be placed in contact with the object the speed of which is to be determined in order to be rotated therewith, a graduated circular scale and a pointer which is geared to the spindle by some suitable reducing- ,gear mechanism. 'These instruments accurately count the speed of the object, while they are in contact with it, but considerable diiculty is experienced in bringing lthe point of the spindle into engagement with the rotating body and in disengaging it therefrom respectively at the beginning and the end of a minute or some other suitable unit of time.

v According to my present invention,1pro vide a clutch between the pointer which is associated with the dial of the counter and the spindle and automatic means for so actuating the clutch as to start and stop the pointerv in response to an electric clock yor some other suitable horological device.

Figure 1 of the accompanying drawings is a plan view of a -speed counter constructed in accordance with my invention.- Fig. 2 is a artially sectional view'correspon ing to F1 1, `witha'p'ortion f the casing remove Fig. 3 is a side elevation, at right angles to Fig. v2,with a' portion ofthe casing removed, and Fig. 4 is an end elevati'on, at right anglesto Fig. 3. Figs. 5 and 6 are detail views, on a larger scale, ofthe clutch mechanism shown in Fig. 2. Fig. 7 is a diagrammatic view of a system embodying the speed counter of the other gi.

ures, a relay device for stopping and starting the counter, anda clock for governing the circuit of the relay device.

Referring to Figs. 1 to 6, inclusive, of the drawings, the counter here shown comprises a spindle 1, having a tip or head 2 which is adapted to engage the end of a shaft 3, or other rotating object, the speed of which is to be determined, a screwthreaded quill or sleeve 4, mounted on the spindle, a pointer or index finger 5, and

suitableV gearing between the sleeve 4 and the pointer. y

The sleeve 4 is interposed between a boss 6 on acasing 7 of the counter, and a collar 8 which is secured to the spindle 1 and is provided with a pin 9 which projects toward the boss 6. The boss 6 is provided with a l similar pin 10 which ,projects toward the collar 8. The ends of the sleeve 4 arev respectively provided with ilanges 11 and 12 having ser1es of perforations 13 and 14 to receive the pins 10 and 9. The sleeve is adapted to slide on the spindle, in response to either one of ,a pair of actuating levers 15 and 16, into engagement with either the pin 9 or the pin 10, but the collar 8 is suiciently spaced from .the boss 6 to prevent any part of-the sleeve being in'contact with both pins at -the same time. When the sleeve is adjusted'into engagement with the pin 9, it is operatively connected to the spindle A1 and rotates with it, but when it is Iadjusted to its opposite position, the pin 10,

. which is a part of the stationary casing or frame of the counter, prevents the rotation of the sleeve. A notched wheel or gear 17 iswsecured to one end-of a transverse shaft 'or pin 18,r to the other end of which the pointer 5 is secured. The notched wheel or gear meshes with the :rewthreaded.sur face of the sleeve 4l constituting a worm gear connection between theV pin or shaft 18 and the spindle 1-. L The lever 16 is pivotally mounted at a point 19 on the casing or frame 7 and is constructed fof magnetizable material sov that it constitutes an armature of an electromagnet 20. When the coil of the electromagnet 20 is ener ized, the lever l16, which is bifurcated an a flange 21 of the sleeve 4, adjusts the sleeve into the. position shown in Fig. 5 of the drawings, in which it is operativelyconnected to the spindle 1. The-lever v15 1sJ acts on J I length of time, breaking the circuit to said coil and instantly energizing the coil oit the magnet 23, is to connect the pointer or 1ndicator 5 to the spindle 1 and then discon` nect it therefrom.

A graduated circular dial 5a is pivotally secured to the frame 7 of the counter, coaxially with the pointer 5 so that its zero mark may be set to correspond to the osition of the pointer at starting. The adpustment ot' the dial is, hoWever,-opposed by sufficient Jfriction to avoid its accidental displacement. rllhe dial may, ot course, be rigidly secured to the trame of the counter and the pointer pivotally secured to its supporting shaft, the arrangement corresponding to a well known connection between the hand of a clock and its spindle. @ther means may bel provided for easily bringing the pointer to a zero reading position relative to the dial preparatory to counting the number of rotations per minute ot a rotating object within the spirit and scope of my invention.

'llie necessity of counting the revolutions or' the pointer which, of course, are few relative to the rotations of the spindle 1, is avoidedby providing a second dial5c and a pointer 5" which coperates therewith and is gearedto the pointer 5 by some suitable reducing gearing, whereby the total .number of rotations per minute of the spindle can be read directly from the two dials even it the device is used to ascertain the number of rotations per minute of a relatively high-speed object. For example: lll* the gear ratio between the pointers 5 and 5b is 20 to 1, and the pointer 5 malres'one complete revolution for 100 rotations ot the spindle 1, then the device can count directly from one to two thousand rotations oit` the spindle.

A spring may be substituted for one ot the magnets 20 and 23, tor actuating the sleeve t in one direction in opposition to the other magnet, but l prefer to use the arthe counter or to the spindle and, consequently, all .ot the partsmay be made very light and the bearings as near frictionlessas rThe pawl ll2 is pivot-ally supporte namens by reason ot the relatively large load which it imposes 'on the moto-r. Furthermore, it is necessary to torce the spindle point ot a -hjand counter against the rotating shaft with such pressure, in order to avoid slipping, as to produce a very undesirable end thrust in the bearings ot the machine under test., None ot these disadvantages appear in the structure oi my present invention.

Referring to Fig. 7 of the drawings, the speed counter shown in the other ngures is here shown diagrammatically with the spindie point engaging the end ot the shaft 3 of an electric motor 25. ln addition to the speed counter and the motor 25, the system shown embodies a relay switch 25, a horological device 27, and storage batteries 28 and 23el which are intended to represent any suitable sources ot electric energy. "lhe relay switch 2G comprises a movable contactI member 29 which is pivoted at a point 30 and is provided with a cross arm 31., and

stationary contact members 32 and 33. A

springy-ll is connected to one end olf thev cross arm 31 and is secured to a post 34 v which is so placed thatthe spring tends to cent notches. y

'lhe positions ot therelay switch, in which contact is made between the parts 29 and 33, are accentuated by the engagement of roller 36 with notches 3'?, while the positions et engagement between the members 29 and 32 are accentuated by the engagement et a roller 39, carried by a pawl t0, with the notches 37. The pawl 40 is provided with a spring t1, in the usual manner. which holds the roller in engagement with the surface of the cam. f A ratchet wheel 43 is secured to the cam 38 and is periodically actuated by a pawl 42.

at the outer yend ot an arm dil which `is secured to and lorms a part ot an armature of an electromagnet 51. The pawl t2` is held against a stop by' a spring 52 which is only i electromagnet 51 is denergized. By perivodically energizing the coil 53, the cam 38 is rotatively moved step-by-step in such manner as to ,make contact Valternately between the member 29 -and the members 33.

and 32.

I prefer to employ an electric clock for the device 27 having a second hand 54 which engages stationary contact members 55 at the beginning and end of each minute and a contact memlber 56 at the' end of the half minute.' ,v

The operation of the`\device is as follows: Assuming that thev second hand 54 1s actuated by an accurate clock mechanism and that the `speed counter is in` operation, the

second hand 54 Will, at the end of a halt minute, engage the Contact member 56, completing a circuit from a terminal 57 of the battery 28a, through conductor58, contact 456, second hand 54, conductor 59,- coil 53 of magnet 51 and conductor 60a t'o the opposite terminal 61a of the battery. The magnet 51 being thus energized, raises the armature 50 and with it the arm and pawl 42 to turn of the battery 28, through conductor 62, contacts 29 and 32, conductor 63, coil of magnet 23 and conductor 60 to battery terminal 61. Magnet 23, vbeing thus energized, acts through lever-15 to move the sleeve 4 and release the pointer 5 from the spindle 1. The engagement of the second hand 54 with the contact 55 at thelvend of the minute again energizes the magnet coil 53 to effect suchl movement of the cam 38 as to permit the roller 36 to fall into one of the notches 37.

`The position of the relayswitch Contact l279 is, therefore, changed to the positionA shown in Fig. 7, and a circuit is completed from the conductor 62, through'the contacts'29 and 33, the conductor 64, the magnet coil 20 and A .and at the Zend lofthe half minute the poin'ter 5 is instantlyl disconnected from the spindle 1 and is prevented from turning by pins 10.- Therefore, byl providing proper gear ratios, the number of revolutions counted, equals the number of revolutions per minute at which the shaft 3 is operating.

In order to make the leading particularlyv accurate it may be worth while to hold the counter in engagement with the shaft dur- .sources will usually be found preferable.

.than any error introduoedby inaccuracies in i ing several i eriods of time and average the readings. he batteries 28 and 28 ma be replaced by -a single source of ,energy 1 desired', -although I believe two lndependent I believe that the variations in thespeed of rotation of the shaft of the machine, even' though the machine is supposed be operating at a constant' speed, will be greater the counter mechanism.

Variations in structure and in the circuit connections of the system may be effected within the Sprit and scope of my invention, and I desire that only such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

1. A speed counter comprising a rotatable member, an indicator, a clock-governed elec-y tromagnetic means for operatlvely connecting the indicator to the rotatable memberat the beginning of a predetermined time interval and a second clock-governed electromagnetic means for disconnecting the rotatable member at the end of such time interval.

2. A speed counter comprising la rotatable spindle an adjustable sleeve supported thereon, an indicator operatively connected to the sleeve, a clock-governed electromagnetic means for so adjusting the sleeve las to operatively connect it to the spindle at the beginning of a predetermined time interval and' a second clock-governed electromagnetic means for disconnecting the sleeve from the spindle at the end of the predetermined time interval.

3. A speed counter comprising a rotatable spindle, an indicator, a clutch for operatively connecting the indicator to the spindle and disconnecting the same therefrom, a pair of electromagnets for actuatingthe clutch, and

a time-governed controller for selectively and successively energizing the electromagnets.

4. A speed counter comprising a rotatable svpindle, an indicator, a clutch for operatively7 connecting the indicator to the spindle and disconnecting the same therefrom, a pair of electro-responsive means for actuating the clutch, and a controller for governing one of the electro-responsive means to start the in dicator at the beginning of a predetermined time interval and for governing the,other electro-responsive means to stop the indicator at theend of such interval.

5. Ar yspeed counter comprising a rotatable spindle, an indicator, a clutch for o eratively connecting the indicator to the splndle and disconnecting it therefrom, two electroles responsive means for selectively Aactuating the clutch, a. clock mechanism` a controller and means dependent upon the clock mechanism for actuating the controller at the bel for governing the electro-responsive means,

iso

ginning and at the time interval.

6.. A speed counter comprising a rotatable spindle, an indicator, a clutch. for operatively connecting the indicator to the spindle and disconnecting it therefrom, tvv-o electro-responsive means for lectively actuating the clutch, an electric clock, a controller for governing the electro-responsive means, and an actuating mechanism dependent upon v the electric clock for changing the position ot end of a predetermined the controller at the beginning and endet a member thereon, a vvorm ivlieel operatively connected between the indicator and the rvvorin screw, La clutch member mounted or the spindle, a clock-governed electromagnet tor soy moving the Worm screw that the clutch member is adapted to engage, vand a second clock-governed electromagnet `for so moving the Worm screw that the clutch members are adapted to disengage.

9. A speed counter comprising a rotatable spindle, an adjustable externally screw threaded sleeve supported thereon, a gear Wheel adapted to engage the screvv threaded sleeve, an indicator actuated by the gear wheel, and clock-governed electromagnetic -v means for so movin the sleeve along the spindle as to operatively connect it to the spindleat the beginning ot a predetermined time interval and disconnect it therefrom at tlfie end of such interval.

ln testimony whereof, l liave hereunto subscribed my name this 5th day or dirne, 1912,

GHARL'ES W. A. Qn'r'riNe,

E. B. Hines. 

